Abrading



Se t. 1, 1925.

J. GOULDBOURN ABRADING Filed Feb. 10. 1922 2 Shah-Sheet 1 .ABRADING F11!Feb. 10. 1 2 aOOtl-shnit 2 lNl/ENTOB To all whom it may concern."

of which the following descriptionyin connection' with the accompanyingdrawings,

i working condition.

Patented Sept. 1; 1925.

- D!S TE PATENT OFFICE.

osErn oounnnoomror. LEICESTER, EivGLANn,1AssIeNon T0 UNITED SHOE MA-cnmmw CORPORATION, or rArnnson, ew JERSEY, A CORPORATION or NEw JERSEYArRAmne.

Application filed February 10, 1922. Serial a. 535,530.

Be itknown that 'I, JOS PH at Leicester, Leicestershire, England,"haveinvented certain Improvementsm'Abradlng,

visa specification, like reference characters on the drawings indicatinglike partsin' the several figures,

hereinshown as embodied in an apparatus for sharpening edge toolssuch,f0r example, as the blades of leather splitting "machines. Theoperation of sharpening suchblades has commonly been a slow handoperation in which it: has not.beenxpossible to hold the tool at aconstant inclination tolthe surface time move the tool in the properpath to,

preserve the abrading element in a good causesit'to become glazed and;wear down in the middle, 'leaving marginal-ridges.

' Important objects of this invention are'to provide an improvedabrading apparatus which will accurately and quickly sharpen tools ofthe nature described and provide for even wear of the'abrjading elementand prevent it fromglazing. In-the illustrated construction theapparatus is substantially automatic and comp rises a flat surfaced oilstone, acarriage, a tool holder pivoted to the carriage,- and mechanismfor actuatingthe carriage in such manner that the tool edge Wlll begiven a series of orbital movements progressively varying in' amplitudeso that the tool edge will traverse the whole surface of the oil stonein a path ofconsiderable complexity'.- The carriage-is moved by a pairof;actuators in the form of crank pins which are revolved at differentspeeds to the end thatfthe tool edge is caused to travel in a series ofnon-coincident orbital paths which atone time he along 'the oil stoneand at other times across it.- Thus oil is worked well in between thetool 3 and the abrading element to, "prevent glazing. Preferably, also",the movement of the edge of the tool is 1 such as to carry it atdifferent times beyond Goomnoonm; asubject of the King of England-,residing This invention relates to abrading and is The regularity of themovement and the tendency to use only the middle portion of the abradingelementall four edges of the abrading-element, thus insuring even wearand preventing the formation of marginal ridges.

and the hone; and various paths of' move ment traversed by the cornersof the knife edge in the course of a complete cycle of movements of theknife edge.

In this machine a hone 1, which may bea plane-surfaced oilstone,"extends across the front of the machine and is clamped-by athumb-screw 2 in a horizontal holder 3 holder 3 to rock on a horizontalaxis and,

the plungers allow a slight tipping lengthwise of the stone. If desired,however, the stone may be prevented from rocking by clamping thetrunnions 4 in their bearings in the upper ends of .the plungers 5 as bymeans of'plates 8, 8 fastened to the upper faces of the'plungers andengaging fiat faces formed on the trunnions. The tipping may also beprevented when desired by clamping the plungers in their bearings in themachine frame as by set screws 9. The edge ofrthe' knife 10 tobe honedis positioned in a holder 11 against gage faces 12 formed on bars 13,13. The bars are pivoted on screws 14, 14 passing through lugs 15, 15formed on the holder 11. The lugs are split to receive the ends of thebars and to allow the screws 14, 14 to clamp apair of adjusting screws16, 16 which bear against the back of the knife to move its edge againstthe gage faces 12.

"In operation the knife is placed on the holder 11 and the screws 14, 14slackened.

screws 14, let until the under faces of the bars rest on the upper faceof the knife. The screws 16, 16 are adjusted to bring the front edge ofthe knife into engagement with the faces 12 on the bars 13 and (afterthe knife is clamped by a clamp screw 20 referred to below) the bars areraised and the'screws 14, 1a tightened to clamp the bars in raisedposition and the screws 16, 16 in adjusted position. I

The knife holder 11 has downwardly projecting lugs 17, 17 which arefulcrumed on a horizontal shaft 18 substantially'in the plane of thesurface of the stone and parallel to the knife edge, and the holder hasa forwardlyextending horizontal arm 19 extending perpendicularly of theknife edge over the-knife and stone, on which is adjustably mounted aweighttnot shown) whereby the knife is pressed down on the stone. Aclamping screw 20 threaded through this arm bears on the top face of theknife to clamp it on the holder.

The horizontal shaft 18 is mounted in lugs 21, 21 projecting upwardlyfrom a member 22 which, towards one end, has a bearing for a verticalcrank pin 23 and, towards its other end, a rectilinear lost motion slot24:, parallel to the knife edge and in which moves a second verticalcrank pin The bearing is on an extension of the line of the slot. Thecrank pins project from collars 26, 26 formed on the upper ends ofvertical shafts 27, 27 carried in bearings formed in the machine frame6. The member.22 is recessed on its lower face to receive the collarsfrom which the crank pins extend, and its plane lower face rests on hardened steel disks 28 housed in the machine frame and respectively looselysurrounding the crank pin shafts 27, 27. To reduce friction, the steelplates rest on ball-races 29 which themselves are supported by steelplates 30 housed in the frame. To support the holder 11 in raisedposition during the removal or positioning of the knife, the

member 22 has projecting rearwardly from it two lugs. 31, 31 which, whenthe knife holder is swung upwardly about the horizontal shaft 18, engagethe downwardly pro jecting lugs 17, 17 on the holder.

The member 22 and holder 11 are given their working movement by thevertical crank-shafts 27, 27 having fixed to their lower ends gearwheels 32, 33 which are driven from a third gear-wheel 3% mounted on thelower end of a vertical shaft 35, positioned centrally between, and tothe rear of, the two vertical crank-shafts and having a bearing in themachine frame. The gearwheel 34 meshes directly with the gearwheel 32and drives the gear-wheel 33 through an idler 36 mounted on the lower.end of a vertical shaft 37 having a bearing in the machine frame. Thegear shaft 35 has, at its upper end, a bevel pinion 38 which meshes witha bevel pinion 39 on the end of a horizontal, rearwardly extending shaft10 mounted in a bearing formed on the machine frame and having, on itsouter end, a driving pulley 41 which may be connected to a suitablesource of power.

To determine the extent of honing to which the knife shall be subjected,a boss 42 is provided on the under side of the knife holder 11, whichboss, as the knife is ground away, encounters a screw 13 threaded intothe member 22 and thereby prevents further downward movement of theholder 11 about the shaft 18 and consequently stops further honingaction. By adjusting the screw the amount of honing action may bevaried.

lVhen honing a knife beveled equally on each side of its edge the knifewill first be honed on one side until the boss 42 and the screw 43 meetand then reversed and the other side honed until the boss and screwagain meet, the boss and screwin this case determining that the edge inthe honed knife is properly located in relation to the body of theknife.

The gear wheels on the lower ends of the crank shafts have respectivelya different number of gear teeth, for example, the gear wheel 32 mayhave thirty-six teeth and the gear 33-thirty-one teeth. Owing to thisdifference in the number of teeth, the crank pins will, during eachrevolution of say the gear 32, gradually change their relative positionsand this change will continue until, after thirty-one revolutions of thegear 32, the relationship of the crank-pins will again be the same as atthe commencement'of the thirty-one revolutions and thereafter thesequence of gradual changes in the relationship of the crank pins willbe repeated. As the movements of the knife holder are positivelycontrolled by the movements of the cranks, the knife edge will move invarying paths, and after thirty-one such movements the sequence ofmovements will be repeated.

During the revolutions of the gears 32 and 33, the movement of the knifeedge is a complex one comprising a series of dissimilar orbitalmovements of different amplitudes, each end of the knife edge tracin a.different complex curve, with the result that honing action between theknife and hone occurs in all directions, sometimes as a result oflargely rectilinear movement, at other times largely as the result ofswinging movement and, at yet other times, as the result of variouscombinations of movements and, consequently, practically the wholesurface of the hone is covered in all directions before the cycle ofmovements begins to be repeated. As a result, oil is worked well betweenthe knife edge and the hone at all times and glazing of its surface isavoided.

Moreover, while the necessary difference ofthe number of teethbetweenthe gears 32 and 33,. one Ofwhichisa relatively high prime number, isestablished to ensure a complex knife path, the difl'eren'ce betweenthese numbers iskept sufiiciently small to ensure that-both endsof theknife receive adequate 'movement. Again, it should be pointed out thatthe face .ofthe knife to be every portion of the hone receives its clueshareof-wear and the formation of marginal ridges on it is avoided.

= JIn Fig. 4- are illustrated some of the com plexpaths traversed by theends of the knife edge. The smallcurves. A show the paths actuallytraversed by the ends of the knife edge during a chosen'first of thethirty-one revolutions of the gear 32 aforementioned,

(being the first revolution from the position shown in Fig. 3) and thelarger curves B show these same paths but to a larger scale. In thecurves B the points marked '1, 1 and 1 indicate the relativepositions'of the opposite ends of the knife edge at different points ofthe paths. The paths Gin dotand-dash lines and the paths .D in dottedlines illustrate, on the larger scale, the paths of movement of the endsof the knife edge during the tenth and twenty-fourth revolution of thegear 32 e., the ninth and twentvthird after that shown by the curves B)respectively and the points 2, 2*, 2 and 3, 3" and 3 indicate relativepositions of the opposite ends of the knife edge at different points inthese paths. The movement of each end of the knife edge is influenced byboth crank pins so that these pathsare more complex than those of thecrank pins.

Although the invention has been shown and described by reference to aspecific em bodiment, it should be understood that the invention is notnecessarily limited thereto. Having thus described my invention, what Iclaim as new and desire to secure by Letters Patent of the United Statesis:

1. A cutting tool sharpening apparatus having, in combination, a planesurfaced abrading element, a tool holder for holding the edge of a toolagainst the abrading ele ment, and mechanism including a plurality ofactuators directly connected with the tool holder for producing relativemovement between the'tool edge and the abrading element in apredetermined irregular path of great complexity.

2. A cutting tool sharpening apparatus having, in combination, a planesurfaced abrading element, a tool holder constructed and arranged topresent a tool to the abrading element at an appropriate inclination,

and mechanisnr including a plurality of actuators movable at differentspeeds and directly connected with the toolholder for moving the tooledge over the abradingelement in a series of non-coincident orbitalpaths to prevent glazing'of the latter.

, having, in combination, an abrading element, a carriage, a tool holderpivoted to the carriage, means topress the edge of a tool in the holderagainst the abrading element, and actuating mechanism for moving v thecarriage through a series of orbital movements progressively varying inamplitude to cause the tool edge to traverse the element in av manner toavoid glazing of the abrasive surface.

5. A blade sharpening apparatus having, in combination, a flat abradingelement, a blade holder for holding a'blade against the abrading elementat a suitable inclination,

' and mechanism for moving the blade holder to insure that the bladeedge will traverse the entire surface of the abrading element to avoidthe formation of marginal ridges upon the latter, said mechanismcomprising two driving elements movable through successive cycles .atdifferent speeds and con nected to impart independent oscillatorymovements to the blade holder.

6. A tool sharpening apparatus having, in combination, an abradingelement, a tool carriage, and mechanism for actuating the carriage tocause a tool edge to traverse a complex path on the abrading element,said mechanism comprising a pair of crank pins, means for causing thecrank pins to revolve at different speeds, and a connection between eachcrank pin and the carriage.

7. A tool sharpening apparatus having, in

combination, an abrading element, a cartraverse a complex path on theabrading.

element, said mechanism comprising a pair of crank pins, gearing forrevolvingt he crank pins at different speeds, and connections betweenthe crank pins and the car riage.

8. A cutting tool sharpening apparatus having, in combination, a planesurfaced abrading element, a tool holder for pressing the tool againstthe abrading element, and mechanism constructed and arranged to move thetool edge over the abrading sur-' face in a series of predeterminedorbital movements of different amplitudes arranged to define acontinuous complex path covering the entire surface of the abradingelement andaoverlapping the entire marginal edge of the abradingsurface.

9. A tool sharpening apparatus having, in combination, a flat abradingelement, a movable support, a tool holder aivoted to the support andmovable toward the support to press a tool on the holder against theabrading element, means comprising a pair of crank pins for actuatingthe support to move the tool over the face of the abrading element, andcooperating means on said holder and said support for. limiting themovement of the tool holder toward the abrading element to stop theabrading action.

10. A blade sharpening apparatus having, in combination, an abradingelement, a blade holder, an arm pivoted to the blade holder and having agage face to contact w th one edge of a blade to be sharpened,

an adjustable member engaging the opposite edge ofthe blade to move thefirst edge into alinement with the gagerlace, and means for clampingthegage arm in an out of the way position.

11. A blade sharpening apparatus having, in combination, an abradingelement, a blade holder, a gage arm pivoted to the blade holder andarranged to contact with the edge of a blade to be sharpened, anadjustable member for engaging the opposite edge of the blade to move itinto contact with the arm, a clamp for securing the blade in adjustedposition on the holder, and a .pivotal mounting for the blade holderwhereby the latter may be swung away from the abrading element wheninserting or removing a blade.

In testimony whereof I have signed my name to this specification.

JOSEPH GOULDBOURN.

